| 摘要 |
The present invention relates to a cutting tool insert for side and face milling of rolled low alloyed steel at low and at moderate cutting speeds comprising a cemented carbide body and a coating. The cemented carbide body comprises WC, 7.3-7.9 wt-% Co and 1.0-1.8 wt-% cubic carbides of Ta and Nb and a highly W-alloyed binder phase with a CW-ratio of 0.86-0.94. The coating comprises
- a first (innermost) layer of TiC x N y O z with a thickness of 0.1-2 µm, and with equiaxed grains with size <0.5 µm
- a layer of TiC x N y O z with a thickness of 2-10 µm with columnar grains with a diameter of about <5 µm
- a layer of TiC x N y O z with a thickness of 0.1-2 µm and with equiaxed or needlelike grains with size ‰¤0.5 µm
- an outer layer of a smooth, textured, finegrained ±-Al 2 O 3 layer with a thickness of 2-10 µm. The invention also relates to the use of such a cutting tool insert for side and face milling of rolled low alloyed steel at low and moderate cutting speeds. |
